NASA Technical Reports Server (NTRS) 20090039403: Tiny Devices Project Sharp, Colorful Images

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by  NASA Technical Reports Server (NTRS)

Tiny Devices Project Sharp, Colorful Images
originating Technology/nAsA Contribution For FLCOS panels to work well, Handschy explains, resulting in a dim appearance. “The Phase II of our NASA
they need a smooth and shiny wafer top surface. Without SBIR came at a very opportune time,” Handschy says.
Johnson Space Center, NASA’s center for the design
this, the pixel mirrors form in the last metal layer on “We were able to have an SXGA [super-extended video
of systems for human space flight, began develop-
the semiconductor wafer, scatter, and then absorb light, graphics array] CMOS backplane we’d designed under
ing high-resolution visual displays in the 1990s for
the NASA project using one of the first commercially
telepresence, which uses virtual reality technology to
available CMP silicon processes.” Chemical mechanical
immerse an operator into the environment of a robot in
planarization (CMP) is a special technique of polishing
another location. Telepresence is used by several indus-
semiconductor wafers to allow more metal layers—and
tries when virtual immersion in an environment is a safer
smoother integrated-circuit surfaces—and was one of the
option, including remote training exercises and virtual
factors that led to Displaytech’s success.
prototyping, as well as remote monitoring of hazardous
Another important development during the mid-
environments. Microdisplay panels, the tiny screens that
1990s was the introduction of efficient blue light-emitting
comprise the visual displays for telepresence, are also used
diodes (LEDs). Displaytech took these bright blue LEDs
in some electronic viewfinders for digital video and still
and combined them with red and green LEDs to illu-
cameras.
minate its panels, rapidly sequencing through the color
partnership LEDs to create the illusion of different hues as they reflect
off the panels. “In this SBIR program, we developed gray-
In 1993, Johnson Space Center granted a Small scale and color for microdisplay panels,” Handschy says,
Business Innovation Research (SBIR) contract to “And that was a first for us. We’ve since leveraged that
Displaytech Inc., based in Longmont, Colorado, and into a line of products.”
recently acquired by Micron Technology Inc., of Boise,
nc. product outcome
Idaho. Under Phase I of this contract, Displaytech began gy I
developing miniature high-resolution displays based on olo Displaytech uses its FLCOS technology to apply
n
its ferroelectric liquid-crystal-on-silicon (FLCOS) tech- Tech active matrix displays (individual switching elements)
nology. Displaytech proposed that pixels could be made on to a tiny silicon chip, with a final product smaller than
cr
small enough to fit a complete high-resolution panel onto Mi a thumbnail. These silicon chips are essentially encased
d
a single integrated circuit. an in a glass window, Handschy says. “There’s this thin layer
c.
Displaytech first determined how to make a panel h In of fast-switching liquid crystal material which allows
that could reproduce grayscale using only standard ytec that circuitry to drive reflective pixels on the surface of
a
complementary metal-oxide-semiconductor (CMOS) pl the chip.”
Dis
logic circuitry, which just recognizes binary values (such of The company’s first microdisplay panels were used
as a “0” for black and a “1” for white) and was not well esy in electronic viewfinders in camcorders and digital still
suited for subtle shades of gray. Dr. Mark Handschy, ourt cameras. Since 1990, Displaytech has shipped over 20
c
Displaytech’s chief technology officer, explains the com- ge million microdisplays to some of the world’s largest con-
a
m
pany perfected time-based grayscale techniques in a Phase I sumer electronics companies, including JVC America,
II follow-on NASA contract: “Because our ferroelectric Ferroelectric liquid-crystal-on-silicon (FLCOS) panels need a the Eastman Kodak Company, Olympus Corporation,
smooth and shiny wafer top surface, which is possible with
liquid crystal material can switch faster than the eye can Hitachi Ltd., Konica Minolta Holdings Inc., Kyocera
chemical mechanical planarization (CMP), a special technique
follow, a sequence of displayed black and white images is Communications Inc., and the Hewlett-Packard
of polishing semiconductor wafers to allow more metal
averaged by the eye into a single grayscale image.” layers—and smoother integrated-circuit surfaces. Company.
86 Consumer, Home, and Recreation Spinoff 2009
Handschy says the company’s LightView products, recently, images and videos displayed on media players
“which all have NASA heritage,” are now being used in and cell phones were constrained by tiny, hard-to-see
a new product: pocket projectors, or “pico” projectors. screens, making it difficult to share images, such as for a
(A pico is a metric unit smaller than a nano.) Until business presentation.
Currently, these pico projectors are sold as separate
“accessory projectors” for existing hand-held devices,
and attach via a universal serial bus cable. (Future media
players and cellular phones will incorporate the pico pro-
jectors in their design and will not need any attachments
for projection.) In these tiny devices, high-brightness
LEDs shine through the microdisplays, magnifying the
tiny images into large, colorful, sharp images 50 inches
across, projected onto walls or screens large enough for
groups of people to view together.
Handschy says the microdisplays are the company’s
most popular products, whether for camera viewfinders
or the new projectors. Currently, camcorders and digi-
tal cameras comprise the main market for Displaytech’s
microdisplays, but pico projectors are soon expected to
dominate the company’s sales.
“We hope to sell a lot more in the new market of
c.
gy In pico projectors,” Handschy says. Displaytech customer
olo 3M currently incorporates the microdisplay in its Micro
n
ch Professional Projector, an accessory projector that weighs
Te
n only 5.6 ounces and is sold in major office suppliers
o
Micr and electronics retailers. Displaytech believes sales of
nd pico projectors may exceed $1.1 billion within 5 years.
a
nc. Today, the company’s research and development is
h I
c funded primarily from product revenue, but Handschy
e
yt
pla says Displaytech is still open to more contracts or
Dis collaborations with NASA.
of
esy In May 2009, Displaytech and Micron Technology
urt Inc. announced Micron’s acquisition of Displaytech to
o
c
e broaden its semiconductor offerings, including products
g
ma for pico projectors. v The individual pixels in Displaytech’s LV-SVGA panels display
I
a greater range of colors than previous microdisplays, due in
Displaytech Inc. uses its FLCOS technology to apply active
part to technology the company developed with an SBIR from
matrix displays to a tiny silicon chip, with a final product Displaytech® is a registered trademark of Micron Technology Inc.
Johnson Space Center.
smaller than a thumbnail. A thin layer of fast-switching liquid LightView™ is a trademark of Micron Technology Inc.
crystal material allows the circuitry to drive reflective pixels on
the surface of the chip.
Spinoff 2009 Consumer, Home, and Recreation 87